In vivo efficacy of JQ1 in cancer cell growth inhibition has been confirmed in mouse models of various cancers including squamous carcinoma (Filippakopoulos et al., 2010), multiple myeloma (Delmore et al., 2011), acute myeloid leukemia (AML) (Zuber et al., 2011), MLL-fusion leukemia (Dawson et al., 2011), castration-resistant prostate cancer (Asangani et al., 2014), breast cancer (Shu et al., 2016), melanoma (Fontanals-Cirera et al., 2017), and inflammation in activated macrophages (Nicodeme et al., 2010). The gene discussed is KMT2A; the disease is acute myeloid leukemia.